Design and sample characteristics of COordinated Oral health Promotion (CO-OP) Chicago: A cluster-randomized controlled trial.

COordinated Oral health Promotion (CO-OP) Chicago is a two-arm cluster-randomized trial with a wait-list control. The primary aim is to evaluate the efficacy of an oral health community health worker (CHW) intervention to improve oral health behaviors in low-income, urban children under the age of three years. Exploratory aims will determine cost-effectiveness, and if any CHW intervention impact on child tooth brushing behaviors varies when CHWs are based out of a medical clinic compared to a community setting.